• Support PF! Buy your school textbooks, materials and every day products Here!

How to calculate current of a resistor inside of another parallel resistor?

  • Thread starter pugfug90
  • Start date
  • #1
118
0
How to calculate current of a resistor "inside" of another parallel resistor?

The 1st image is how he drew it for us, no text.. I guess because it's quite complicated.
He asks a bunch of questions, I've answered..
1. Equivalent resistance of R3 and R4=5 ohms
2. combined resistance of R6 and R7=9 ohms
3. combined resistance of R9 and R10? =9 ohms
4. equivalent resistance from D to E? 3 ohms
5. Equivalent resistance from B to E?
---
this one was kind of tricky.. but I think I got it right.. 5 ohms? I calculated the equivalent resistances of R(3,4) and R(6,7,8,9,10), added it to R5.. Now, R(3-10) acts parallel to R2... blah blah, 5 ohms for R(2-10).
6. total resistance? 5 ohms of the parallels and 2 and 1 makes 8.
7. total current? 3A
8. Potential drop occurs across R1? 6V
9. Drop in potential from B to E? 15V
10. Current in R2? 1.5A
:confused: 11
Current in R5? How come I got R2 but not R5?
"9. Drop in potential from B to E? 15V"
Vt in parallel is equal to "everything", by everything, meaning "one and one".. or something.. So yeah, I'm positive that V2 is 15V.. and V(3-10) is 15V.. But how do I find the V5 to find out the I5.. Thanks..
--
Also just figured that I(3-10)=1.5A..
"$ 1 5.0E-6 10.391409633455755 50 5.0 43
w 64 368 64 208 0
v 64 208 64 176 0 0 40.0 24.0 0.0
w 64 176 64 96 0
w 64 96 144 96 0
r 144 96 176 96 0 2.0
w 176 96 272 96 0
w 272 96 272 192 0
r 272 192 272 240 0 10.0
w 272 240 272 368 0
w 272 368 208 368 0
r 208 368 176 368 0 1.0
w 176 368 64 368 0
w 272 96 480 96 0
w 480 96 480 112 0
w 480 112 416 112 0
w 480 112 544 112 0
r 544 112 544 144 0 10.0
r 416 112 416 144 0 10.0
w 416 144 480 144 0
r 480 144 480 176 0 2.0
w 544 144 480 144 0
w 480 176 544 176 0
w 480 176 416 176 0
r 416 176 416 192 0 7.0
r 544 176 544 192 0 6.0
w 416 192 416 208 0
w 544 192 544 208 0
r 416 208 416 224 0 2.0
r 544 208 544 224 0 3.0
w 416 224 480 224 0
w 480 224 480 208 0
r 480 208 480 192 0 9.0
w 480 176 480 192 0
w 544 224 480 224 0
w 480 224 480 368 0
w 480 368 272 368 0"
http://www.falstad.com/circuit/
This has confirmed my other answers.. still wanna know number 11 and past, how to do them.
 

Attachments

Last edited:

Answers and Replies

  • #2
118
0
Meh.. anyhow, I came upon kind of a breakthrough..
I got 15V for the voltage of the non serialized resistors.. An in a parallel, all "total" resistors have equal voltage.. So V2 equals V(3-10[sans 2])
15V=V2=V(3-10[sans2)..
With V2, and te given R2, I got I2 of 1.5A.. and in a circuit, total current is equal to current of the series, or the sum of the parallel's.. So if It=3A..and I2=1.5A.. V(3-10[sans2])=1.5A.. and since R5 is in a series with R(3-4), R(6-10), it's current is equivalent to the other's.. So V5=1.5A?? And yeah..couple hours til I get to his class anyhow..
 
  • #3
118
0
Case closed..and the rest of the answers that I came up with match the falstad.com data thing;;:)
 

Related Threads on How to calculate current of a resistor inside of another parallel resistor?

Replies
3
Views
3K
  • Last Post
Replies
12
Views
3K
Replies
5
Views
4K
Replies
12
Views
5K
Replies
13
Views
2K
Replies
7
Views
2K
Replies
4
Views
22K
  • Last Post
Replies
3
Views
226
Replies
2
Views
6K
Top